U.S. patent application number 11/023682 was filed with the patent office on 2005-06-30 for hexagonal array structure of dielectric rod to shape flat-topped element pattern.
Invention is credited to Ahn, Do-Seob, Kang, Byung-Su, Kim, Yang-Su, Ku, Bon-Jun, Park, Jong-Min.
Application Number | 20050140559 11/023682 |
Document ID | / |
Family ID | 34698619 |
Filed Date | 2005-06-30 |
United States Patent
Application |
20050140559 |
Kind Code |
A1 |
Kim, Yang-Su ; et
al. |
June 30, 2005 |
Hexagonal array structure of dielectric rod to shape flat-topped
element pattern
Abstract
A hexagonal array structure of a dielectric rod for shaping a
flat-topped element pattern (FTEP) is provided. The hexagonal
structure of dielectric rods forming a flat-topped element pattern
(FTEP) includes: a center element for forming a unit radiation
pattern of the FTEP through an electromagnetic wave mutual coupling
by receiving a polarization signal of a basic mode; a plurality of
first ring elements arranged at vertexes of a regular hexagon based
on the center element for forming the unit radiation pattern by
electromagnetic wave mutual coupling with the center element and an
electromagnetic wave; and a circular waveguide array supporting
unit for supporting the center element and the plurality of first
ring elements.
Inventors: |
Kim, Yang-Su; (Daejon,
KR) ; Kang, Byung-Su; (Daejon, KR) ; Ku,
Bon-Jun; (Daejon, KR) ; Park, Jong-Min;
(Daejon, KR) ; Ahn, Do-Seob; (Daejon, KR) |
Correspondence
Address: |
BLAKELY SOKOLOFF TAYLOR & ZAFMAN
12400 WILSHIRE BOULEVARD
SEVENTH FLOOR
LOS ANGELES
CA
90025-1030
US
|
Family ID: |
34698619 |
Appl. No.: |
11/023682 |
Filed: |
December 27, 2004 |
Current U.S.
Class: |
343/785 ;
343/776 |
Current CPC
Class: |
H01Q 21/067 20130101;
H01Q 13/24 20130101 |
Class at
Publication: |
343/785 ;
343/776 |
International
Class: |
H01Q 013/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 27, 2003 |
KR |
10-2003-0098389 |
Claims
What is claimed is:
1. A hexagonal structure of dielectric rods forming a flat-topped
element pattern (FTEP), comprising: a center element for forming a
unit radiation pattern of the FTEP through an electromagnetic wave
mutual coupling by receiving a polarization signal of a basic mode;
a plurality of first ring elements arranged at vertexes of a
regular hexagon based on the center element for forming the unit
radiation pattern by electromagnetic wave mutual coupling with the
center element and an electromagnetic wave; and circular waveguide
array supporting means for supporting the center element and the
plurality of first ring elements.
2. The hexagonal structure of dielectric rods as recited in claim
1, further comprising: a circular waveguide unit including a
polarizer for generating polarization by feeding an input signal to
the center element; a dielectric rod for radiating a signal passed
through the circular waveguide unit; and six dielectric rod
elements for forming the FTEP by the electromagnetic wave mutual
coupling, wherein the six dielectric rod elements are the first
ring elements.
3. A hexagonal structure of dielectric rods forming a flat-topped
element pattern (FTEP), comprising: a center element and a
plurality of first ring elements for forming a unit radiation
pattern of the FTEP through an electromagnetic wave mutual coupling
by receiving a polarization signal of a basic mode; a plurality of
second ring elements arranged at vertexes of a regular triangle
grating having one or two first ring elements as a vertex of the
regular triangle and forming a shape of a regular hexagon for
forming a radiation pattern by mutual coupling with the center
element and the first ring elements; and circular waveguide array
supporting means for supporting the center element, the plurality
of first ring elements and the plurality of second ring
elements.
4. The hexagonal structure of dielectric rods as recited in claim
3, further comprising: a circular waveguide unit including a
polarizer for generating a polarization by feeding an input signal
to the center element and six of the first ring elements; six of
dielectric rods included in a center dielectric rod and the first
ring elements radiating a signal passed through the circular
waveguide unit; and twelve of dielectric rod elements for forming
the FTEP by the electromagnetic wave mutual coupling, wherein the
twelve of dielectric rod elements are the second ring elements.
5. A hexagonal structure of dielectric rods forming a flat-topped
element pattern (FTEP), comprising: a plurality of elements from a
center element to 6(N-1) elements of a (N-1).sup.th ring for
forming a unit radiation pattern of the FTEP by electromagnetic
wave mutual coupling by receiving a polarization signal of a basic
mode; 6N elements of Nth ring for forming a unit radiation pattern
by being arranged within a regular space and being electromagnetic
wave mutual coupled with adjacent element; and circular waveguide
array supporting means for supporting a plurality of elements from
the center element to Nth ring, wherein N is a natural number.
6. The hexagonal structure of dielectric rods as recited in claim
5, further comprising: a circular waveguide unit including a
polarizer for generating a polarization by feeding an input signal
to elements from the center elements to the 6(N-1) elements of the
(N-1).sup.th ring; 6(N-1) of dielectric rods included in the (N-1)
rings radiating a signal passed through the circular waveguide unit
and a center dielectric rod for radiating a signal passed through
the circular waveguide unit; and 6N of dielectric rod elements for
forming the FTEP by the electromagnetic wave mutual coupling,
wherein the 6N of dielectric rod elements are the elements of the
N.sup.th ring.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a hexagonal array structure
of a dielectric rod for shaping a flat-topped element pattern
(FTEP); and, more particularly, to a hexagonal array structure of a
dielectric rod for shaping a flat-topped element pattern (FTEP) for
having a wide beam scanning range and a constant electric
performance generated from a strong electromagnetic wave mutual
coupling by arranging a dielectric rod at a vertex of a regular
hexagon as a center dielectric rod and arranging a predetermined
size of dielectric rods around the center dielectric rod.
DESCRIPTION OF RELATED ARTS
[0002] According to a Korea publication No. 10-2002-11503, entitled
"Two dimensional multi layers circular radiation array structure
for forming FTEP", a phase control element is a major and expensive
element for developing a phased array antenna. The number of the
phase control elements is determined according to a gain of an
antenna array, a side lobe level and a required sector beam scan
angle. The gain of the antenna array and the level of side lobe are
used for determining a shape or a size of an array aperture. Also,
the required sector beam scan angle is used for determining a
distance of array element space.
[0003] Also, when a conventional phase control element is designed,
a maximum array space of the phase control elements is determined
for preventing to generate a grating lobe in a real space in order
to wide beam scanning.
[0004] In contrary, in a flat-topped element pattern (FTEP) scheme,
the maximum array space is determined for preventing to generate
the grating lobe in the real space since it has comparative narrow
beam scanning range .+-.5.degree. or 25.degree.. And, the grating
lobe can be suppressed by a side lobe characteristic of the FTEP.
Accordingly, the space between phase control elements becomes
comparatively wider and thus the number of the phase control
elements can be minimized. For example, when a phase array
requiring 20.degree. of a cone shape beam scanning is designed, the
number of phase control elements can be reduced to 1/11 by using
the FTEP scheme. Inhere, for forming FTEP within a required beam
scanning range, an amplitude array characteristic of an array
aperture must be satisfied to have overlapped sub-array. Also, the
amplitude characteristic of array aperture must be satisfied to 1
sin x x
[0005] for an one-dimensional array, 2 sin x x sin y y
[0006] for a two-dimensional array, and 3 J 1 ( x ) x
[0007] for a three-dimensional array.
[0008] For obtaining the above-mentioned characteristic, five
conventional array structures have been introduced as follows.
[0009] FIGS. 1A to 1H are diagrams showing conventional array
structures having a passive multiport network. As shown in FIG. 1A,
the conventional array structure having the passive multiport
network includes a phase shifter 110 for providing a required phase
difference between an input signal and an output signal in a beam
shaping unit and a beam directioning unit in a phase array antenna
system, an antenna array element 120, a multiport network 130 for
forming a required amplitude and a phase distribution for the FTEP
by being inserted between the phase shifter 110 and the array
element 120. FIGS. 1B to 1H show embodiments of the conventional
array structure having various multiport networks. However,
according to the conventional array structures in FIGS. 1A to 1H, a
feeding network is too complicated when it is implemented for the
two-dimensional scanning. Accordingly, the conventional array
structures shown in FIGS. 1A to 1H have disadvantages such as
decrease of efficiency, large volume, heavy weight and high system
cost.
[0010] FIG. 2A is a diagram illustrating a conventional electric
plane linear array scanning structure and FIG. 2B is a diagram
showing a conventional magnetic plane linear array scanning
structure. A dual mode waveguide has an advantage of simplifying an
antenna array design for exciting required modes by using slots of
a waveguide wall since the dual mode waveguide includes a common
wall. The conventional electric plane linear array scanning
structure of FIG. 2A and the conventional magnetic plane linear
array scanning structure of FIG. 2B include a single mode waveguide
210, 211 having a predetermined diameter a.sub.0 for filtering a
microwave, a matching waveguide 220, 221 having a predetermined
diameter at for providing an impedance matching between the single
mode waveguide 210, 211 and a dual mode waveguide 230 and 231, and
the dual mode waveguide 230 and 231 for mutual-coupling electric
power by using dual slots. However, the conventional electric plane
near scanning structure and the conventional magnetic plane linear
scanning structure have comparative narrow bandwidth and a small
beam scanning range. Also, it is limited to be implemented in a one
dimensional.
[0011] FIGS. 3A to 3C are diagrams showing wrinkled waveguide array
structures in accordance with a related art. As shown in FIGS. 3A
to 3B, the wrinkled waveguide array structure includes an array
element 310, 311 for receiving a signal from external, and a
reactive load 320, 321 having a reactive impedance and having a
function of a reflective termination to the array element 310, 311.
In the wrinkled waveguide array structures, only few of array
elements is directly connected to a phase control element and
remained array elements are connected to the reactive load.
Radiation from a passive radiation element connected to the
reactive load is generated by reflection of the reactive load and
mutual coupling between the active radiation elements directly
connected to the phase control element. FIGS. 3A and 3B shows a
reflection step generated by one repetition unit b. For forming the
FTEP, sufficient coupling is required and additional passive
scatterer may be equipped at upper of aperture. However, the
wrinkled waveguide array structure requires a plurality of phase
shifters since the space of the array elements is 0.7 to 0.85
.lambda. and it is impossible designing more than 3% array antenna.
Also, the wrinkled waveguide array structure has disadvantages such
as large volume, heavy weight and high system cost.
[0012] FIG. 4 is a diagram showing a two dimensional multi circular
radiation array structure disclosed at Korea publication No.
10-2002-11503.
[0013] As shown in FIG. 4, in the two-dimensional multi circular
radiation array structure, a predetermined size (2r) of circular
shape dielectric disks are arranged in a repeated unit (dx) of a
regular triangle grating and stacked as N-layers within a regular
space (ds) in a direction of a wave propagation direction.
Therefore, a mutual electromagnetic wave coupling is naturally
generated between a center feeding element and feeding elements
arranged around of the center feeding element. Since the two
dimensional multi circular radiation array structure is
comparatively complicated to be manufactured and a successful
synchronization is required for arranging disks and stocking the
disks.
SUMMARY OF THE INVENTION
[0014] It is, therefore, an object of the present invention to
provide a hexagonal array structure of a dielectric rod for shaping
a flat-topped element pattern (FTEP) for having a wide beam
scanning range and a constant electric performance generated from a
strong electromagnetic wave mutual coupling by arranging a
dielectric rod at a vertex of a regular hexagon as a center
dielectric rod and arranging a predetermined size of dielectric
rods around the center dielectric rod.
[0015] In accordance with an aspect of the present invention, there
is also provided a hexagonal structure of dielectric rods forming a
flat-topped element pattern (FTEP), including: a center element for
forming a unit radiation pattern of the FTEP through an
electromagnetic wave mutual coupling by receiving a polarization
signal of a basic mode; a plurality of first ring elements arranged
at vertexes of a regular hexagon based on the center element for
forming the unit radiation pattern by electric wave mutual coupling
with the center element and an electromagnetic wave; and a circular
waveguide array supporting unit for supporting the center element
and the plurality of first ring elements.
[0016] In accordance with another aspect of the present invention,
there is also provided a hexagonal structure of dielectric rods
forming a flat-topped element pattern (FTEP), including: a center
element and a plurality of first ring elements for forming a unit
radiation pattern of the FTEP through an electromagnetic wave
mutual coupling by receiving a polarization signal of a basic mode;
a plurality of second ring elements arranged at vertexes of a
regular triangle grating having one or two first ring elements as a
vertex of the regular triangle and forming a shape of a regular
hexagon for forming a radiation pattern by mutual coupling with the
center element and the first ring elements; and a circular
waveguide array supporting unit for supporting the center element,
the plurality of first ring elements and the plurality of second
ring elements.
[0017] In accordance with an aspect of the present invention, there
is also provided a hexagonal structure of dielectric rods forming a
flat-topped element pattern (FTEP), including: 6(N-1) elements
including elements from a center element to a (N-1).sup.th ring for
forming a unit radiation pattern of the FTEP by electromagnetic
wave mutual coupling by receiving a polarization signal of a basic
mode; 6N of N ring elements for forming a unit radiation pattern by
being arranged within a regular space and being electromagnetic
wave mutual coupled with adjacent element; and a circular waveguide
array supporting unit for supporting the 6(N-1) elements and the
plurality of N ring elements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The above and other objects and features of the present
invention will become better understood with regard to the
following description of the preferred embodiments given in
conjunction with the accompanying drawings, in which:
[0019] FIGS. 1A to 1H are diagrams showing conventional array
structures having a passive multiport network;
[0020] FIG. 2A is a diagram illustrating a conventional electric
plane linear array scanning structure;
[0021] FIG. 2B is a diagram showing a conventional magnetic plane
linear array scanning structure;
[0022] FIGS. 3A to 3C are diagram showing wrinkled waveguide array
structures in accordance with a related art;
[0023] FIG. 4 is a diagram showing a two dimensional multi circular
radiation array structure disclosed at Korea publication No.
10-2002-11503;
[0024] FIG. 5A is a side elevation view showing a hexagonal array
structure of a dielectric rod for shaping a flat-topped element
pattern (FTEP) in accordance with a preferred embodiment of the
present invention;
[0025] FIG. 5B is cross sectional view of a hexagonal array
structure of a dielectric rod for shaping a flat-topped element
pattern; and
[0026] FIG. 5C is an upper side elevation view of a hexagonal array
structure of a dielectric rod in accordance with a preferred
embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0027] Hereinafter, a hexagonal array structure of a dielectric rod
for shaping a flat-topped element pattern (FTEP) in accordance with
a preferred embodiment of the present invention will be described
in more detail with reference to the accompanying drawings.
[0028] FIG. 5A is a side elevation view showing a hexagonal array
structure of a dielectric rod for shaping a flat-topped element
pattern (FTEP) in accordance with a preferred embodiment of the
present invention. FIG. 5B is cross sectional view of a hexagonal
array structure of a dielectric rod for shaping a flat-topped
element pattern and FIG. 5C is an upper side elevation view of a
hexagonal array structure of a dielectric rod in accordance with a
preferred embodiment of the present invention.
[0029] The hexagonal array structure of a dielectric rod includes a
center element 510, six of first ring elements 520, twelve of
second ring elements 530 and a circular waveguide array supporting
unit 540.
[0030] When a basic mode signal is feed through a polarizer 512 to
the center element 510 and the six first rings 520, an electric
distribution satisfying a requirement is formed on the twelve
second elements 530 and an antenna aperture by electromagnetic wave
mutual coupling of twelve second ring elements 530. Also, a FTEP
radiation pattern is formed at a far-field region. The center
element 510 includes an input circular coaxial cable 511, a
polarizer 512 and a dielectric rod 513.
[0031] The input circular coaxial cable 511 feeds an input signal
and the polarizer 512 is a thin dielectric plate located inside a
circular waveguide and forms a required polarization. The
dielectric rod 513 forms a traveling wave and radiates the
traveling wave signal. Also, the dielectric rod 513 forms a unit
radiation pattern forming the FTEP by the electromagnetic wave
mutual coupling.
[0032] The center element 510 and each of the first ring elements
520 form the FTEP unit radiation pattern by mutually coupling to
the second ring elements 530. The first ring elements 520 are
arranged around the center element 510. The space between the first
ring elements 520 is d.sub.x and d.sub.y, and accordingly,
locations of the first ring elements in a x y coordinate are
(d.sub.x, d.sub.y), (d.sub.x, -d.sub.y), (-d.sub.x, d.sub.y)
(-d.sub.x, -d.sub.y), (0, 2d.sub.y), (0, -2d.sub.y). The second
ring elements are arranged at a vertex of regular triangle having
one or two first ring elements as a vertex. That is, the second
ring elements form a second hexagonal. Locations of the second ring
elements in a x y coordinate are (2d.sub.x, 0), (-2d.sub.x, 0),
(2d.sub.x, 2d.sub.y), (2d.sub.x, -2d.sub.y), (d.sub.x, 3d.sub.y),
(d.sub.x, -3d.sub.y), (0, 4d.sub.y), (0, -4d.sub.y), (0, 2d.sub.y),
(0, -2d.sub.y), (-d.sub.x, 3d.sub.y), (-d.sub.x, -3d.sub.y) as
shown in FIG. 5C.
[0033] The center element 510 and the six first ring elements
include the polarizer 512 for generating polarization and twelve
second ring elements do not include the polarizer 512.
[0034] As mentioned above, the present invention can suppress the
grating lobe and decrease the number of radiation elements by
arranging a dielectric rod at a vertex of a regular hexagon as a
center dielectric rod and arranging a predetermined size of
dielectric rods around the center dielectric rod for shaping a
flat-topped element pattern (FTEP). Therefore, the present
invention can decreases a cost of antenna system, feeding loss and
can be implemented to a comparative wide beam scanning.
[0035] Also, the present invention can be easily implemented for a
millimeter bandwidth (more than 10 GHz) and would comparatively
light by fixing constant size of dielectric rod at a waveguide.
[0036] While the present invention has been described with respect
to certain preferred embodiments, it will be apparent to those
skilled in the art that various changes and modifications may be
made without departing from the spirits and scope of the invention
as defined in the following claims.
* * * * *